Power operated device



June 11, 1963 v. COLT ETAL 3,093,168

POWER OPERATED DEVICE 4 Sheets-Sheet 1 Filed Feb. 16, 1960 IN V EN TORSVicfor L. 60/) Char/es B WII/ac/r Buck/yarn, Cheat/70m 8 Flora MAATTORNEYS United States Patent 3,093,163 POWER OPERATED DEVHIE Victor L.Colt and Charles B. Willock, Portland, Greg, assignors to The PetersCompany, Portland, Greg, a partnership Filed Feb. 16, 1960, Ser. No.9,083 12 Qlatrns. (Cl. 143-37) The present invention relates to a poweroperated device and more particularly to a control mechanism for a poweroperated device having a plurality of individually shiftable loadelements.

It is a principal object of the present invention to provide a poweroperated device having a plurality of load elements mounted in alongitudinally extending series with means for selectively shiftingcertain of said load elements and at the same time maintaining apredetermined relationship between at least certain of the load elementsupon such shifting.

Another object of the invention is to provide a power operated deviceincluding a plurality of load elements and an individual motor formoving each of such load elements and in which a new .and novel controlsystem is provided enabling manual adjustment of the position of any oneof such load elements while automatically maintaining the same relativepositioning between the shifted element and at least certain of theother load elements.

A more particular object of the invention is to provide a new andimproved saw mill edger.

A further object is to provide a new and improved arrangement forpositioning the adjustable saws of a saw mill edger.

Another object is to provide a new and improved control system for a sawmill edger.

Still other objects and advantages of the invention will become moreapparent hereinafter.

In accordance with the illustrated embodiment of the invention, a sawmill edger is provided with a plurality of circular saws shiftablymounted upon an arbor with a plurality of hydraulic motors, eachincluding a cylinder and a piston connected one to each of the saws forshifting the same. An operator control means is provided to enableshifting of any one of the saws to a predetermined position relative toan .adjacent saw. Sensor means are provided for each saw to enable themovement of an adjacent saw to be detected and which sensor means isoperable to effect certain maintenance of spacing between the saws.

'For a more detailed description of the invention, reference is made tothe accompanying drawings, wherein:

FIG. 1 is a front elevation partly broken away of a saw mill edgerincorporating the invention;

FIG. 2 is a fragmentary sectional view taken substantially along line 22of FIG. 1 showing certain details of the invention;

FIG. 3 is an enlarged sectional view taken substantially along line 33of FIG. 2;

FIG. 4 is an enlarged, fragmentary perspective view showing certaindetails of the arrangement for shifting the saws of the edger;

FIG. 5 is an enlarged, fragmentary sectional view taken substantiallyalong line 55 of FIG. 1;

FIG. 6 is a fragmentary, semi-schematic, perspective view of certain ofthe control mechanisms of the invention;

FIG. 7 is a view of an operators control panel and saw positioningindicators;

FIG. 8 is an elevation of a portion of the control arrangement and motormeans of the invention taken substantially along line 88 of FIG. 9;

FIG. 9 is a sectional view taken substantially along line 99 of FIG. 8;

FIG. 10 is an enlarged sectional view taken substantially along line101tl of FIG. 8 showing a detail of the control mechanism; and

FIG. 11 is a circuit diagram of a control circuit utilized in thepresent invention.

The present invention is illustrated as adapted to an edger for trimmingand slitting slabs in a saw mill. The illustrated edger includes a framehaving a base 10 upon which are mounted a pair of side plates 12, 14rotatably supporting in suitable journals a saw arbor 16 upon which aremounted a plurality of saws including a base saw 20 and shiftable saws22, 24, 26 and 28. As indicated, the arbor i6 is fluted and the saws areeach provided with a cooperatively fluted hub 30 so that the saws willbe driven as the arbor rotates. A motor 32 is provided for driving thearbor 16 and for providing power to suitable feed rolls to carry theslabs tln'ough the edger and past the saws. Since the feed rolls form nopart of the present invention and are well known in the art (see, forexample, the patent to L. I. Peter, No. 2,507,644), they are not shownin the present drawings.

The saw 20 is fixed in position upon the arbor 16 by any suitable means,but each of the saws 22, 24, 26 and 28 is movable longitudinally of thearbor and each is straddled by a saw shifting member comprising a pairof arms 34 extending forwardly from a shifting bar 36. The arms 34 arespaced to provide a slot slightly wider than the saw blade and areprovided with hard wood or fiber inserts 33 which preferably arethreadedly mounted in the arms 34 and adjusted so as lightly to brushthe opposite smooth surfaces of the saw. As will be evident, lateralshifting of a shifting bar 36 will result in shifting of thecorresponding saw along the arbor 16.

For the purposes of illustrating the invention, the saws 22, 24, 2'6 and28 represent a plurality of load elements mounted in a longitudinallyextending series and which are shiftable relative to predeterminedpositions relative to each other and to .a fixed element positioned atone end of the series, the fixed element in this case comprising thefixed or base saw 20.

To effect shifting of the saws 22, 24, 26 and 28, the edger is providedwith a plurality of motor means including a first member fixedly securedto the frame of the edger and a second member movable relative to theframe. The illustrated motor means comprise .a plurality of cylinders42, 44, 4-6 and 48 fixedly secured to the base by frame members 49(FIGURE 4), each of which cylinders is provided with a reciprocablepiston having a piston rod 50 extending from an end of the correspondingcylinder. The rods of the cylinders 42, '44, 46 and 48 are connected toshift the saws 22, 24, 26 and 28, respectively. The end of each of thepiston rods 50 is bolted or otherwise suitably secured to a dependingbracket 54 on the end of one of the shifting bars 36. Each of theshifting bars 36 is slidably supported on the frame of the machine by apair of oppositely projecting arms 56, each of which has a horizontallyextending portion 58 having a guide bushing 60 projecting upwardlytherefrom and which fits within one of a pair of longitudinallyextending grooves 62 (FIGURE 5) formed within a guide member 64.Extending upwardly from one side of the portion 58 of each arm is aflange 66, the flanges of a pair of arms being arranged to embraceopposite sides of the guide member 64 as best shown in FIG. 5. Eachflange 66 has a guide element 68 projecting therefrom and which engagesin a cooperative groove 74] formed in the corresponding side surface ofthe guide member 64.

As will be evident, selective admission of fluid to the opposite ends ofthe cylinders 42, 44, 46 and 48 will cause the pistons thereof (to moveand to shift the saws 22, 24, 26 and 28 along the arbor 16. A suitablehydraulic circuit for operating the cylinders is shown schematically inFIG. 11 and will be described in detail hereinafter.

In accordance with the present invention, control means are provided forthe motors or cylinders 42, 44, 46 and 48, which control means includeoperator controlled switch means which are operable to actuate aselected one of the cylinders to move a selected one of the shif-tablesaws a predetermined distance along the arbor. A sensor means is alsoprovided for each saw and which is operable to detect shifting movementof the saw next adjacent thereto on the side toward the base saw. Suchsensor means is operable upon actuation to shift its corresponding saw adistance equal to and in the direction of the movement of the detectedsaw. In other words, with reference to FIG. 2, means are provided sothat when saw 22 is shifted in either direction along the arbor, thesaws 24, 26, 28 will be shifted in like direction and the same distanceso as to maintain identical spacing between the saws 22, 24, 26, 28. Onthe other hand, if an operator shifts saw 24, saws 26 and 28 willlikewise shift, and if an operator shifts the saw 26, only the saw 28will be automatically shifted therewith. These features of the controlmeans and others will now be described in detail.

With particular reference to FIGS. 4, 6 and 9, extending parallel toeach of the cylinders 42, 44, 46, 48 and immediately above each is aswitch actuating bar indicated at 72, 74, 76 and 78, respectively. Asmore particularly shown in FIG. 4, the bar 72 is secured to the bracket54 to which the piston rod of the cylinder 42 is connected so that anymovement of the piston of the cylinder 42 will 'be imparted to the bar72. The bars 74, 76 and 78 are connected in similar fashion to thebracket 54 to which the piston rod of the corresponding cylinder isconnected. The opposite ends of the switching bars 72, 74, 76, 78 aresupported upon transversely extending supporting elements 82, 84, 86,88, respectively, provided at their opposite ends with bifurcated guides90 which straddle longitudinally extending support rods 92.

Secured at one end to an end plate 94 is a switch supporting member 102which is positioned immediately above the path of the switching bar 72.The opposite end of the member 102 is connected to a bar 104 (FIG URE 6)having bifurcated guides at its opposite ends straddling oppositesupport rods 1G5. Fixedly secured to the opposite side surfaces of themember 102 are a plurality of pairs of switch mounting plates, therebeing four pairs shown 106, 108, 110, 112. Mounted upon each of theseplates is an electrical switch having an actuator element dependingbelow the plate in position to be engaged and raised by the switchingbar 72 as it moves beneath the switch to actuate the same. The plates106 carry a normally open switch 120 and a normally closed switch 122and which have actuator elements indicated (FIGURES 8 and at 120' and122, respectively. The plates 108 support a normally open switch 124 anda normally closed switch 126 having actuators 124' and 126,respectively. The plates 110 support a pair of switches 128, 130,normally open and closed, respectively, and which have actuator elements128' and 138, respectively. The plates 112 support a pair of switches132, 134 which are normally open and normally closed, respectively, andhave actuator elements 132', 134', respectively. The switches of eachpair are arranged so that the actuator element of the normally closedswitch of such pair is contacted first as the switching bar moves to theleft as shown in FIG. 8 and the actuator element of the normally openswitch of such pair is contacted immediately thereafter. Such movementof the switching bar 72 will take place when the saw 22 is being shiftedtoward the base saw 20. The reverse will be true when the saw 22 isshifted away from the base saw 20.

A similar set of switches is provided for cooperative action with theswitching bar 74. Such switches are mounted upon a switch support member140 which is supported at one end by the supporting element 82 for theswitching bar 72 and thus the switch support member 140 is moved as theswitching bar 72 moves. The purpose of this will be explainedhereinafter. The opposite end of the switch support member 140 issecured to a transverse support member 141 (FIGURES 6 and 8) havingbifurcated guides at its opposite ends slidably engaging the supportrods 105. The switch supporting member 149 has secured thereto aplurality of pairs of switch mounting plates 144, 146, 148 and 150. Eachpair of plates supports a normally closed and a normally open switchhaving actuator elements in position to be engaged and operated by theswitching bar 74 as it moves longitudinally relative to such switches.The actuator elements of the normally open and normally closed switchesof such series are arranged in the same manner as the switches mountedon the switch supporting bar 102. The switches on the member 140 areindicated in FIG. 11, those supported on plates 144 being 151 and 153;those on plates 146 being switches 155 and 157; those on plates 148being switches 159 and 161; and those on plates 150 being switches 163and 165, the first named switch in each pair being a normally openswitch, the second named being the normally closed switch.

Similar series of switches are mounted upon switch supporting members167, 169 secured at one end to the sup porting elements 84, 86,respectively, and slidably supported at their opposite ends from therods by supporting elements 171, 173, respectively.

The spacing between each successive pair of switches is equal to thedesired increments of movement of the shiftable saws 22, 24, 26, 28.Thus in the illustrated embodiment and refening to FIG. 8, the pairs ofswitches on the support member 102 are mounted at two inch intervalsfrom one another and the switches 120, 122 are arranged so that the endof the switching bar 72 will engage the actuator 122' and move theswitch 122 to open position, but is just short of engagement with theactuator for switch 120 when the saw 22 is four inches from the base saw20. The switches 124, 126 are arranged so that when the saw 22 is movedto a position six inches from the base saw 20, the switch 124 willremain in its normally open condition but normally closed switch 126 isopened. The switches 128, are in similar position so that when the saw22 is eight inches from the base saw 20, the switch 128 will remain openand normally closed switch 130 will be opened. The switches 132, 134 aresimilarly arranged so that the normally open switch 132 will remain openand the normally closed switch 134 will be opened when the saw 22 is teninches from the base saw 20. The switches on the switch mounting bar arealso arranged so that the normally closed switch of a pair will beopened and the normally opened switch will be unclosed when the saw 24is at desired increments of distance from the saw 22, such spacing maybe, for example, at 4, 6, 8 and 10 inches. The switches for the othersaws will be similarly positioned on their respective mounting bars.

With reference to FIGS. 1, 7 and 9, operator control over thepositioning of the saws is attained by means of a plurality of operatorswitches mounted in the control panel indicated generally at 160. In theillustrated embodiment of the invention, the control system is arrangedto permit adjusting of each shifta'ble saw to any one of four differentpositions with respect to an adjacent saw. Thus, for the saw 22, fourswitches 162, 164, 166, 168 are provided by means of which the operatorcan cause the saw 22 to be positioned at four inches, six inches, eightinches or ten inches, respectively, from the base saw 20. A similarseries of switches 174, 176, 178 and 180 is provided for enablingpositioning of the saw 24 at four inches, six inches, eight inches orten inches, respectively, from the saw 22. Other switches are indicated,but not specifically identified for controlling the position of the saws26 and 28 from the saws 24, 26, respectively.

Immediately above the control panel is provided a series of indicatorswhich visually show the operator the relative position of each saw.Referring to FIGS. 6 to 9, attached to and extending upwardly from theswitch supporting element 141 is an arm 182 to which is attached at itsupper end an indicator plate 184 (FIGURE 7) having a pointer 186 whichcooperates with iudicia 188 positioned on the frame structure of theedger to show the position of the saw 22 relative to the base saw 20*.The indicator 184 is elongated and has a scale marked thereon.Similarly, the supporting elements 171, 173 have arms 192, 194,respectively, secured thereto and which arms extend upwardly and supportindicators 196, 198, respectively. Indicator 196 has a pointer 200cooperatively arranged with the scale on the plate 184 to indicate therelative position of the saw 24 with respect to the saw 22. Theindicator 198, on the other hand, has a pointer 202 which iscooperatively arranged with a scale on the indicator 196 to show therelative position of the saw 26 with respect to the saw 24. To indicatethe position of the saw 28 relative to saw 26, an arm 204 is secured tothe switch bar 78. The arm 204 supports a pointer 206 which cooperateswith a some on the indicator 198 to show the spacing between the saws26, 28.

Shown in FiG. 11 are suitable electrical and hydraulic circuits formaintaining control over the saw 24, the circuits being in the conditionassumed with the saw 24 positioned eight inches from the saw 22. Poweris supplied through suitable lines indicated at 220, 222. Operatorswitch 174 is provided with a pair of normally closed contacts 224, 226,the former of which is connected by a lead 228 to line 220. Contact 226is connected by a lead 230 to a normally closed contact 232 of operatorswitch 176. The other normally closed contact 234 of switch 176 isconnected by a lead 236 to a norm-ally closed contact 238 of operatorswitch 178. The other normally closed contact 240 of switch 178 isconnected by a lead 242 to one side of operator switch 180. The switch174 is provided with a pair of normally open contacts 244, 246, thefirst of which is connected by a lead 248 to the lead 228. The switch176 has a pair of normally open contacts 250, 252, the former of whichis connected by a lead 254 to the lead 238. Lead 236 is connected by alead 254 to a pair of normally open contacts 256, 258 for switch 178.Switch 180 is also provided with a pair of normally open cont-acts 260,262, the former of which is connected to the lead 242. Contact 246 ofswitch 174 is connected by a lead 266 to the coil 268 of a relay 270having two pairs of normally open contacts 272, 274 and 276, 278. Thecontacts 272 and 276 are also connected to the lead 266. The contact 274is connected by a lead 284 to an indicator lamp 286 which is in turnconnected to the power line 220 by a lead 288. The contact 252 of switch176 is connected by a lead 290 to the winding 292 of a relay 294 havingtwo pairs of normally open contacts 296, 298 and 300, 302 and a pair ofnormally closed contacts 308, 310. The contact 298 is connected by alead 312 to an indicator lamp 314, the opposite side of which isconnected by a lead 316 to line 230. Normally open contacts 296 and 300are connected directly to the lead line 298. The normally closed contact308 is connected by a lead 318 to the winding 268 of relay 27 0.Normally open contact 258 of switch 178 is connected by a lead 322 toone side of the winding 324 of a relay 326. Relay 326 which is shown inits activated condition has two pairs of normally open contacts 328, 330and 332, 334. The relay also hzfi a pair of normally closed contacts340, 342. Normally open cont-acts 328 and 332 are connected directly tolead line 322. Normally closed contact 340 is connected by a lead 344 tonormally closed contact 310 of relay 294 and by a lead 346 to thewinding 292 of relay 294. The contact 330 is connected to lead 236 bylead 335, indicator lamp 333 and lead 331. Normally open contact 262 ofswitch 180 is connected by a lead 350 to one side of .the winding 352 ofa relay 354, the opposite side of the winding being connected by a lead356 to the power line 222. Relay 354 has two pairs of norm-ally opencgntacts 358, 360 and 362, 364; It also has a pair of normally closedcontacts 370, 372. Normally open contacts 358 and 362 are connecteddirectly to the lead line 350. Normally closed contact 370 is connectedby a lead 374 to the normally closed contact 342 of relay 326 and by alead 376 to the winding 324 of relay 326.

Redirecting our attention to relay 270, the normally open contact 278thereof is connected by a lead line 380 to the contact 382 of switch 151and the contact 384 of switch 153. The other contact 386 of switch 151is connected by a lead line 388 to one side of the operating coil 390 ofa fourway hydraulic valve 392. The opposite side of the coil 390 isconnected by a lead 394 to power line 222. The operation of -a valve 392will be described in greater detail subsequently. A contact 396 ofswitch 153 is connected by a lead 398 to one side of the operating coil400 for the valve 392, the opposite side of the coil being connected bythe lead 402 to the power line 222.

Normally open contact 302 of relay 294 is connected by a lead 484 to acontact 406 of normally open switch 155 and to a contact 403 of normallyclosed switch 157. The other contact 410 of switch 155 is connected by alead 412 to the lead line 388. Contact 413 of switch 157 is connected bya lead 414 to a lead 416 which is in turn connected to the line 398.

Normally open contact 334 of relay 326 is connected by a lead 417 tonormally open contact 418 of switch 159 and to normally closed con-tact420 of switch 161. The contact 422 of switch 159 is connected by a lead424 to the lead 388. The other contact 426 of switch 161 is connected bya lead 428 to the lead 416.

Normally open contact 364 of relay 354 is connected by a lead 430 to anormally open contact 432 of switch 163, the other contact 434 of theswitch being connected by lead 436 [to the lead 388. The lead 430 isalso connected to contact 438 of normally closed switch 165, the othercontact 440 thereof being connected to the lead 416..

A pump for supplying fluid to the cylinders 42, 44,46, 48 is indicatedat 450 in FIG. 11. The pump is adapted to supply fluid to an accumulatorindicated at 452 which is connected by a conduit 454 to a port 456 inthe valve 392. The valve 392 is shown in accordance with the 111C. codeand it will be recognized that the valve is a spool valve. Fluid isreturned to the pump 450 through a conduit 458 connected to a port 460of the valve.

The valve 392 is provided with a further pair of ports 462, 464. Theport 462 is connected by a conduit 466 to one end of the cylinder 44while the port 464 is connected by a conduit 467 to the opposite end ofthe cylinder 44. The valve 392 is shown in its inactive position, thatis with no cross connection between the ports 456, 460 and the ports462, 464.

The valve 392 is provided, however, with port connecting passageportions including a straight through portion 468 and a flow reversingportion 4711. Upon energization of the coil 390, the valve is operatedto bring the reversing portion 470 into position with the ports 456,468, 462 and 464. This causes fluid to flow from the accumulator 452through the conduit 454 to port 456 and through the valve to port 464,then through conduit 467 into the left end of cylinder 44 causing thepiston thereof to move to the right. Such movement will, of course,force fluid out of the opposite end of the piston through the conduit466 to the port 462, then through the valve and out of the port 460through the conduit 458 to the pump 450.

On the other hand, energization of the coil 400 will bring the straightthrough portion 468 of the valve in line with the valve ports. In thiscondition, fluid will flow into the port 456 of the valve, through thevalve, and out from the port 462, through the conduit 466 to theright-hand end of the cylinder 44 to cause the piston to move to theleft. Such movement of the piston will cause fluid to be forced out ofthe left-hand end 7 of the cylinder and be carried through the conduit467 .to the port 464 through the valve to the port 460 and back to thepump 450.

Operation of Electrical Circuit The circuit is shown in a staticcondition wherein as mentioned above, the saw 24 is positioned eightinches from the saw 22. If we assume that the operator wishes to changethe position of the saw 24 and move it to a position four inches fromthe saw 22, he will depress the operator button 174. This will break theholding circuit for the relay 326 which normally extends from the line220 through the lead 228, contacts 224, 226 of switch 174, lead 230,contacts 232, 234 of switch 176, lead 236, lead line 331, indicator lamp333, lead line 335, contacts 330, 328 of relay 326, lead 322, coil 324of relay 326, lead 376, normally closed contacts 370, 372 of relay 354and lead 356 to the opposite power line 222. Upon breaking of thiscircuit, the relay 326 will drop out opening contacts 328, 330 and 332,334 at the same time closing contacts 340, 342. Depression of the switch174 will also cause a circuit to be closed from the line 220 throughleads 228, 248, contacts 244, 246 and lead 266 to the coil 268 of therelay 270. This circuit continues through lead 318, normally closedcontacts 308, 310 of relay 294, lead 344, normally closed contacts 340,342 of relay 326, lead 374, normally closed contacts 370, 372 of relay354 and line 356 back to the opposite power line 222. Energization ofthe coil 268 will actuate the relay 270 closing all of the contactsthereof. This will close the holding circuit from the power line 222including lead 288, indicator lamp 286, lead 284, contacts 274, 272,lead 266 back through the coil 268 of the relay and through the normallyclosed contacts of the other relays to the lead 356 and finally powerline 222. Operation of the relay 270 will also close a circuit throughthe coil 400 of the valve 392. This circuit extends from the power line220 through lead 288, lamp 286, lead 284, contacts 274, 272, lead 266,then back through now closed contacts 276, 278 of relay 270, lead 380,through the closed contacts 384, 396 of switch 153, lead 398, coil 400,lead 402 to the opposite power line 222. As described before, energizingof the coil 400 will cause the valve 392 to operate to pass fluid intothe right-hand side of the cylinder 44 causing the piston thereof tomove to the left. This will also cause the switching bar 74 to move tothe left and which as it goes will, in order, close switch 159, openswitch 157 and close switch 155. These actions will have no eflect uponthe circuit. However, eventually, the switching bar 74 will open switch153. This will immediately open the circuit through the coil 400de-energizing the same and the valve 392 will return to its neutralposition stopping the piston of the cylinder 44 so that the switchingbar will stop and the saw 24 also will stop and at which time it will befour inches from the base saw 20. However, if by accident the switchingbar 74 moves too far to the left and closes the switch 151, the coil 390of the valve 392 will be energized. The circuit for this extends fromthe line 220 through the lead 288, lamp 286, lead 284, through contacts274, 272 of the relay 270, and back through the relay contacts 276, 278to lead 380, through now closed contacts 382, 386 of the switch 151 andthrough lead 388, coil 390 and lead 394 to the power line 222. Thiswill, of course, cause the fluid to be passed to the left-hand of thecylinder 44 and move the piston to the right. As soon as the switchingbar 74 clears the switch 151 to permit it to drop out, the circuitthrough the coil 390 will be opened de-energizing the coil andpermitting the valve 392 to return to its neutral position, stopping themovement of the piston and the cylinder 44. Thus, the saw 24 will beaccurately positioned at four inches from the saw 22 with the switchingbar in such position that it retains the switch 153 open while switch151 remains in its normally open position.

If the operator had desired to move thesaw 24 from a position eightinches from the saw 22 to a position at six inches from such saw, thiswould be accomplished by depressing the operator button 176 to activatethe relay 294. In a manner similar to that described previously, acircuit across contacts 300, 302 of relay 294 would have been closed andthrough switch 157 to energize coil 400 of valve 392 whereupon thecylinder 44 would operate to move the saw 24 toward the saw 22. When theswitching bar 74 opened the switch 157, the valve 392 would havereturned to its normal condition stopping movement of the piston in thecylinder 44.

If we assume a circuit condition as shown in FIG. 11 and wherein the saw24 is positioned eight inches from the saw 22, to move the saw 24 to aposition ten inches from the saw 22, swtich 180 is depressed. This willclose the circuit from the power line 220 through the switches 164, 166and .168 to lead 242 and through the now closed contacts 260, 262 of theswitch, then through the lead 350 and the coil 352 of the relay 354 andthen through the lead 356 to the power line 222. Upon energization ofcoil 352, the relay will actuate to close contacts 358, 360 and 362, 364and to open contacts 370, 372. When the contacts 370, 372 open, theholding circuit through the relay 326 will open causing the relay todrop out opening the circuits across contacts 328, 330 and acrosscontacts 332, 334. At the same time, the circuit across contacts 340,342 of relay 326 will be closed. Upon actuation of the relay 354, aholding circuit for the relay will be established extending from thepower line 220 through the switches 164, 166, .168 through lead 351, thesignal lamp 353, lead 355, across now closed contacts 360, 358 throughlead 350 to the coil 352, then through lead 356 to the power line 222. Acircuit will also be closed through the actuating coil 390 of the valve392. This last circuit extends from the lead 350 which, it will beremembered, is hot, through now closed contacts 362, 364 of the relay354, through lead 430, across the closed contacts 432, 434 of the switch163 through lead 436 to lead 388, then through the coil 390 and lead 394to the power line 222. Energization of the coil 390 will cause the valveto move the portion 470 across the valve ports causing fluid to flowthrough the conduit 467 to the lefthand side of the cylinder 44. This inturn will cause the piston to move to the right to move the saw 24 andthe switching bar in the same direction. The switching bar 74 willcontinue to move to the right until it clears the actuating pin for theswitch 163 permitting the switch to drop out. When the switch 163 dropsout, the circuit through the coil 390 will open and the valve 392 willreturn to its inactive position stopping the flow of fluid to thecylinder 44 and thus stopping movement of its piston. If momentum shouldcause the assembly of the saw 24 to move too far to the right and beyondthe ten inch position, the switching bar 74 will move from beneath theswitch 165 permitting it to close. This will establish a circuit fromthe hot line 350 through the now closed contacts 362, 364 of the relay354 and then through the line 430 to closed contacts 438, 440 of theswitch and through lead 416, the coil 400 and lead 402 to the power line222. This will cause the valve 392 to operate and direct fluid throughthe conduit 466 to the right-hand end of the cylinder 44 and move thepiston and switching bar 74 to the left. The switching bar 74 will moveonly until the switch 165 is again opened breaking the circuit throughthe coil 400 whereupon the valve 392 will return to its inactiveposition and fluid flow to the cylinder 44 ceases stopping movement ofthe piston. Substantially similar control circuits are provided forcontrolling adjustment of the position of the other saws and areoperated in the same manner. While the illustrated circuit is forobtaining adjustment of a saw to one of four positions, it will beobvious the circuit may be modified to permit adjustment to any desirednumber of positions.

Simultaneous Shifting of Saws It will be recalled that an object of theinvention is upon shifting of any given saw to cause all of the sawswhich are on the side of such shifted saw opposite the base saw 20 toshift a corresponding distance. To demonstrate how this is accomplishedwith the illustrated embodiment of the invention, we will assume aninitial condition as illustrated, that is, with the saw 22 positionedeight inches from the base saw 20 and with the saw 24 positioned eightinches from the saw 22. If the operator should now operate the controlcircuit for the saw 22 to cause it to move to a position six inches fromthe base saw '26, the motor 42 would be caused to operate and shift thesaw and would cause the switching bar 72 to move a corresponding amountand also cause the switch supporting member 140 to move to the leftrelative to the switching bar 74. With reference to FIGS. 6 and 11, thiswould mean shifting of the switch 161 to the left of the switch bar 74and as the switch actuator element clears the end of the switch bar 74,it is apparent that it will close. This will close a circuit through theoperating coil 400' of the valve 39-2 and which circuit extends from thepower line 220 through the switches 174, 176 to the leads 236, 331, thesignal light 333, lead 335, through the now closed contacts 330*, 328 toline 322, then through the closed relay contacts 332, 334, through lead417, closed contacts 420, 426 of the switch 161 and then through leads4-28, 416 and 398 to the coil 400, then through lead 402 to the powerline 222. Upon energization of the coil 4%", the valve 392 will operateto shift the valve portion 468 across the ports of the valve causingfluid to be directed through the conduit 466 to the right-hand of thecylinder 44. This will cause the piston thereof to shift to the left andalso cause the switching bar 74 to shift to the left. It is evident thatthe piston of cylinder 44 will continue to operate so long as the switchassemblies continue to move to the left. When the saw 22 has reached itsstationary position six inches from the base saw 20 and the switchsupporting member 140 stops movement and becomes stationary, theswitching member 74 will eventually reopen the switch 161. This, ofcourse, will break the circuit through the valve coil 29% causing thevalve 392 to return to its neutral position and stop the motor '44 andat which time the saw 24 will be eight inches from the saw 22 or thesame distance as it was before the position of the saw 22 was changed.In similar manner and at the same time, the saws 26, 28 will be shiftedto the left to maintain the same spacing between the saws 24, 26, 28 aswas present before any change was made in the position of the saw 22.

If the saw 22 were moved from its initial position of eight inches fromthe base saw 20 to a position of ten inches, the saws 24, 26, 28 wouldmove to the right. Such shifting of the saw 22 would, for example, movethe assembly of the switches on the switch supporting bar 146 to theright relative to the switching bar 74. This would cause the switch 159to close as its actuator element rode up over the end of the switchingbar 74 causing a circuit to be closed through the coil 390 of the valve392. This circuit is established from the power line 220 through theswitches 174, 176, leads 236, 331, indicator lamp 333, lead 335, closedrelay contacts 330, 328 to line 322, closed relay contacts 332, 334 andline 417 through closed switch contacts 418, 422, leads 424, 388, coil3% and lead 394 to the power line 222. Energization of coil 390 willmove the valve portion 470 across the valve ports causing fluid to flowthrough the conduit 467 to the left end of the cylinder 44 whereupon thepiston thereof and saw 24- will move to the right, together with theswitching bar 74. When the saw 22 reaches its eventual position teninches from the base saw 20, its motion will be arrested and theswitches carried by the switch supporting bar Ml) will stop. The motor44- will continue to operate, however, until the switching bar '74clears the switch 159 allowing it to drop out which will open thecircuit through the coil 396 and permit the valve 392 to return to itsneutral position stopping operation of the motor 44 with the saw 24-positioned eight inches from saw 22. In like manner, the saws 26 and 28will be shifted to the right to maintain the original spacingtherebetween.

In like manner to the operation described above, saws 24, 2'6 and 28 canbe adjusted in their individual positions upon the arbor 16 and in likemanner to the procedure described, upon shifting of the saw 24, saws 26and 28 will be shifted a like amount or upon shifting of the saw 26, thesaw 28 will be shifted a like amount along the arbor 16.

It is possible that under some conditions of spacing between the saws,the selected spread between the base saw 20 and the saw 23 would begreater than permitted by the arbor 16. In such a case, the motor 48 forthe saw 28 would simply urge the saw to its farthest possible positionto the right on the arbor 16 until the circuit conditions change to movethe saw 28 to the left. Obviously, a suitable overt-ravel switcharrangement could be provided also.

Having illustrated and described a preferred embodiment of theinvention, it should be apparent to those skilled in the art that theinvention permits of modification in arrangement and detail. We claim asour invention all such modifications as come within the true spirit andscope of the appended claims.

We claim:

1. In a device including a frame and having a plurality of load elementssupported on said frame in a longitudinally extending series andshiftable to predetermined positions relative to each other and to afixed element positioned at one end of said series, a plurality of motormeans each including a first member fixedly secured to said frame and asecond member movable relative to said frame and connected one to eachof said load elements for shifting the same, control means for saidmotor means responsive to predetermined signals to actuate one of saidmotor means to shift the corresponding load elements a predetermineddistance longitudinally of said series, and means responsive to andoperable upon shifting of any one of said load elements to cause themotor means connected to the load element next adjacent said one loadelement on the side away from said fixed element to operate and effectmovement of said last mentioned load element a distance equal to and inthe direction of the movement of the said one load element.

2. In a device having a plurality of load elements mounted in alongitudinally extending series and shif-table to predeterminedpositions relative to each other and to a fixed element positioned atone end of said series, a plurality of motor means connected one to eachof said load elements for shifting the same, and control means for saidmotor means including means responsive to predetermined signals toactuate a predetermined one of said motor means to shift thecorresponding load element a predetermined distance longitudinally ofsaid series, said control means including an actuatable sensor means foreach of said load elements for detecting shifting movement of the loadelement nexlt adjacent thereto on the side toward said fixed element,and means responsive to actuation of said sensor means operable tooperate the motor means of the corresponding load element to eifectmovement of said last mentioned load element a distance equal to and inthe direction of the movement of the said load element next adjacentthereto on the side toward said fixed element.

. In a device including a frame and having a plurality of load elementssupported on said frame in a longitudinally extending series andshiftable to predetermined positions relative to each other and to afixed element positioned at one end of said series, a plurality ofcylinders fixedly mounted on said frame, a piston in each of saidcylinders connected one to each of said load elements for shifting thesame, control means for said cylinders responsive to predeterminedsignals to cause movement of any selected one of said pistons to shiftthe corresponding load element a predetermined distance longitudinallyof said series, and means responsive to and operable upon shifting ofany one of said load elements to cause the piston connected to the loadelement next adjacent thereto on the side away from said fixed elementto be driven relative to its cylinder and to shift the load elementconnected to said last mentioned piston a distance equal to and in thedirection of the movement of the said one load element.

4. In a power operated device having a pair of load elements shiftablerelative to one another and to a fixed element along a predeterminedpath, said load elements including a first load element and a secondload element, said first load element being positioned between saidsecond load element and said fixed element, a pair of reversible motormeans connected one to each of said load elements for shifting the same,control means for said motor means including a plurality of operatorcontrolled switches for each motor means selectively operable to movesaid first load element to any one of a plurality of predeterminedpositions relative to said fixed element and to move said second loadelement to any one of a plurality of predetermined positions relative tosaid first element, and means operative upon shifting of said first loadelement automatically to shift said second load element an identicalamount, said last mentioned means comprising a plurality of pairs ofswitches mounted in a longitudinally extending series, and operativelyconnected to one of said load elements for shifting movement therewith,one of the switches of each pair being for the purpose of controllingmovement of a load element in one direction and the other switch beingfor the purpose of controlling movement of such load element in theopposite direction, a switch operating member operatively connected tothe other of said load elements for shifting movement therewith andoperatively associated with said series of switches to operate the sameseriatirn as said switches and operating member move relative to oneanother, and means connecting said switches to said motor means andoperable upon operation of one of the switches of each of said pairsupon shifting of said first load element in a predetermined direction tooperate the motor means for said second element so as to shift saidsecond load element in the same direction and operable upon operation ofthe other switch of each of said pairs to operate the motor means forsaid second load element so as to shift said second load element in theopposite of said predetermined direction.

5. An edger or the like comprising an arbor, a plurality of shiftablecircular saws mounted on said arbor and slidable therealong betweenpredetermined operating positions relative to one another and to a fixedelement at one end of said series, a plurality of motor means connectedone to each of said shiftable saws for shifting the same on said arbor,and control means for said motor means including operator switch meansoperable to actuate one of said motor means to move a selected one ofsaid shiftable saws a predetermined distance on said arbor, said controlmeans including an actuatable sensor means for each of said shiftablesaws for detecting shifting movement of the saw next adjacent thereto onthe side toward said fixed element, and means responsive to actuation ofsaid sensor means operable to operate the motor means of thecorresponding saw to effect movement of said last mentioned saw adistance equal to the distance of movement of the said saw next adjacentthereto on the side toward said fixed element.

6-. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a plu rality of shiftable circular sawsmounted on said arbor and slidable therealong between predeterminedoperating positions, a plurality of motor means connected one to each ofsaid shiftable saws for shifting the same on said ar-bor, and controlmeans for said motor means including operator controlled switch meansselectively operable to actuate said motor means to move a selected oneof said shiftable saws a predetermined distance on said arbor, saidcontrol means including an actuatable sensor means for each of saidshiftable saws for detecting shifting movement of the saw next adjacentthereto on the side toward the base saw, and means responsive toactuation of said sensor means operable to operate the motor means ofthe corresponding saw to effect movement of said last mentioned saw adistance equal to the distance of move ment of said saw next adjacentthereto on the side toward the base saw.

7. An edger or the like comprising a frame, an arbor, a base saw mountedon said arbor adjacent one end thereof, a plurality of shiftablecircular saws mounted on said arbor and slidable therealong betweenpredetermined operating positions, a plurality of saw shifting memberseach engaging one of said shiftable saws for shifting the same on saidarbor, a plurality of cylinders fixedly mounted on said frame and pistonmeans for each cylinder each including a reciprocable piston rod, eachof said piston rods being operatively connected to a separate one ofsaid saw shifting members, a source of actuating fluid, a plurality ofvalve means operable for controlling the flow of actuating fluid fromsaid source to said cylinders to effect movement of said piston rods,and control means for said valve means including a plurality of operatorcontrolled switches for each saw selectively operable to move ashiftable saw a predetermined distance on said arbor, and meansoperatively connected to said valve control means operable upon shiftingof a given saw to operate the cylinders and pistons of each of the sawsmore remote from said base saw to shift such more remote saws acorresponding distance so as to maintain the same spacing between suchremote saws as was present prior to the shifting of said given saw.

8. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a plurality of shiftable circular sawsmounted on said arbor and slidable therealong between predeterminedoperating positions, a plurality of cylinder and piston meansoperatively connected one to each of said shiftable saws for shiftingthe same on said arbor, a source of actuating fluid, a plurality ofvalve means operable for controlling the flow of actuating fluid fromsaid source to said cylinder and piston means to effect movement of saidshiftable saws, and control means for said valves including operatorcontrolled switch means for each saw selectively operable to move ashiftable saw a predetermined distance on said arbor, said control meansincluding an actutable sensor means for each of said shiftable saws fordetecting shifting movement of the saw next adjacent thereto on the sidetoward said base saw and means responsive to actuation of said sensormeans operable to operate the said valve means of the cylinder andpiston means for the corresponding saw to etfect movement of saidcorresponding saw a distance equal to and in the direction of themovement of the said saw next adjacent thereto on the side toward thebase saw.

9. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a plurality of shiftable circular sawsmounted on said arbor and slidable therealong between predeterminedoperating positions, a plurality of saw shifting members each engagingone of said shiftable saws for shifting the same on said arbor, aplurality of cylinder and piston means each including a reciprocablepiston rod, each of said piston rods being operatively connected to aseparate one of said saw shifting members, a source of actuating fluid,a plurality of valve means operable for controlling the flow ofactuating fluid from said source to said cylinders to effect movement ofsaid piston rods, and control means for said valve means including aplurality of operator controlled switches for each saw selectivelyoperable to move a shiftable saw a predetermined distance on said arbor,said control means including actuatable sensor means for each of saidshiftable saws for detecting shifting movement of the saw next adjacentthereto on the side toward said base saw, and means responsible toactuation of said sensor means operable to operate the said valve meansof the cylinder for the corresponding saw to effect movement of thepiston thereof and said corresponding saw a distance equal to and in thedirection of the movement of the said saw next adjacent thereto on theside toward the base saw.

10. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a pair of shiftable circular sawsmounted on said arbor and slidable therealong including a first saw anda second saw, said first saw being mounted between said second saw andsaid base saw, a pair of reversible motor means connected one to each ofsaid shiftable saws for shifting the same on said arbor, control meansfor said motor means including a plurality of operator controlledswitches for each motor means selectively operable to move said firstsaw to any one of a plurality of predetermined positions relative tosaid base saw and to move said second saw to any one of a plurality ofpredetermined positions relative to said first saw, and means operativeupon shifting of said first saw automatically to shift said second sawan identical amount, said last mentioned means comprising a plurality ofpairs of switches mounted in a longitudinally extending series, andoperatively connected to one of said shiftable saws for shiftingmovement therewith, one of the switches of each pair being for thepurpose of controlling movement of a load element in one direction andthe other switch being for the purpose of controlling movement of suchload element in the opposite direction, a switch operating memberoperatively connected to the other of said shiftable saws for shiftingmovement therewith and operatively associated with said series ofswitches to operate the same ser-iatim as said switches and operatingmember move relative to one another, and means connecting said switchesto said motor means and operable upon operation of one of the switchesof each of said pairs upon shifting of said first saw in a predetermineddirection to operate the motor means for said second saw so as to shiftsaid second saw in the same direction and operable upon operation of theother switch of each of said pairs to operate the motor means for saidsecond saw so as to shift said second saw in the opposite of saidpredetermined direction.

11. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a pair of shiftable circular sawsmounted on said arbor and slidable therealong including a first saw anda second saw, said first saw being mounted between said second saw andsaid base saw, means for shifting said shiftable saws on said arborincluding a pair of cylinder and piston means each including areciprocable piston rod, each of said piston rods being operativelyconnected to a separate one of said saws, a source of actuating fluid,valve means operable for controlling the flow of actuating fluid fromsaid source to said cylinders to elfect movement of said piston rods,and control means for said valves including a plurality of operatorcontrolled switches for each saw selectively operable to move said firstsaw to any one of a plurality of predetermined positions relative tosaid base saw and to move said second saw to any one of a plurality ofpredetermined positions relative to said first saw, and means operativeupon shifting of said first saw automatically to shift said second sawan identical amount, said last mentioned means comprising a plurality ofpairs of switches mounted in a longitudinally extending series, andoperatively connected to one of said shiftable saws for shiftingmovement therewith, one of the switches of each pair being for thepurpose of controlling movement of a load element in one direction andthe other switch being for the purpose of controlling movement of suchload element in the opposite direction, a switch operating memberoperatively connected to the other of said shiftable saws for shiftingmovement therewith and operatively associated with said series ofswitches to operate the same seriatim as said switches and operatingmember move relative to one another, and means connecting said switchesto said valve control means and operable upon operation of one of theswitches of each of said pairs upon shifting of said first saw upon saidarbor in a predetermined direction to supply fluid to the cylinder ofsaid second saw so as to shift said second saw in the same direction andoperable upon operation of the other switch of each of said pairs tosupply fluid to the cylinder of said second saw so as to shift saidsecond saw in the opposite of said predetermined direction.

12. An edger or the like comprising an arbor, a base saw mounted on saidarbor adjacent one end thereof, a pair of shiftable circular sawsmounted on said arbor and slidable therealong including a first saw anda second saw, said first saw being mounted between said second saw andsaid base saw, means for shifting said shiftable saws on said arborincluding a pair of cylinder and piston means each including areciprocable piston rod, each of said piston rods being operativelyconnected to a separate one of said saws, a source of actuating fluid,valve means operable for controlling the flow of actuating fluid fromsaid source to said cylinders to effect movement of said piston rods,control means for said valves including a plurality of operatorcontrolled switches for each saw selectively operable to move said firstsaw to any one of a plurality of predetermined positions relative tosaid base saw and to move said second saw to any one of a plurality ofpredetermined positions relative to said first saw, and means operativeupon shifting of said first saw automatically to shift said second sawan identical amount, said last mentioned means comp-rising a pluralityof pairs of switches mounted in a longitudinally extending series andoperatively connected to said first saw for shifting movement therewith,one of the switches of each pair being for the purpose of controllingmovement of a load element in one direction and the other switch beingfor the purpose of controlling movement of such load element in theopposite direction, and means operatively associated with said series ofswitches to operate the same seriatim as said switches and operatingmember move relative to one another, and means connecting said switchesto said valve control means and operable upon operation of one of theswitches of each of said pairs upon shifting of said first saw upon saidarbor in a predetermined direction to upply fluid to the cylinder ofsaid second saw so as to shift said second saw in the same direction andoperable upon operation of the other switch of each of said pairs tosupp-1y fluid to the cylinder of said second saw so as to shift saidsecond saw in the opposite of said predetermined direction.

References Cited in the file of this patent UNITED STATES PATENTS2,507,644 'Peters May 16, 1950 2,518,813 Pearson Aug. 15, 1950 2,745,446Deiry et al. May 15, 1956 2,830,629 Deiters Apr. 15, 1958 2,894,545Wirth July 14, 1959 2,918,951 Haumann Dec. 29, 1959 FOREIGN PATENTS502,048 Canada May 4, 1954 567,994 Canada Dec. 23, 1958 282 Sweden June12, 1885

3. IN A DEVICE INCLUDING A FRAME AND HAVING A PLURALITY OF LOAD ELEMENTSSUPPORTED ON SAID FRAME IN A LONGITUDINALLY EXTENDING SERIES ANDSHIFTABLE TO PREDETERMINED POSITIONS RELATIVE TO EACH OTHER AND TO AFIXED ELEMENT POSITIONED AT ONE END OF SAID SERIES, A PLURALTIY OFCYLINDERS FIXEDLY MOUNTED ON SAID FRAME, A PISTON IN EACH OF SAIDCYLINDERS CONNECTED ONE TO EACH OF SAID LOAD ELEMENTS FOR SHIFTING THESAME, CONTROL MEANS FOR SAID CYLINDERS RESPONSIVE TO PREDETERMINEDSIGNALS TO CAUSE MOVEMENT OF ANY SELECTED ONE OF SAID PISTONS TO SHIFTTHE CORRESPONDING LOAD ELEMENT A PREDETERMINED DISTANCE LONGITUDINALLYOF SAID SERIES AND MEANS RESPONSIVE TO AND OPERABLE UPON SHIFTING OF ANYONE OF SAID LOAD ELEMENS TO CAUSE THE PISTON CONNECTED TO THE LOADELEMENT NEXT ADJACENT THERETO ON THE SIDE AWAY FROM SAID FIXED ELEMENTTO BE DRIVEN RELATIVE TO ITS CYLINDER AND TO SHIFT THE LOAD ELEMENTCONNECTED TO SAID LAST MENTIONED PISTON A DISTANCE EQUAL TO AND IN THEDIRECTION OF THE MOVEMENT OF THE SAID ONE LOAD ELEMENT.